1. Field of the Invention
The present invention relates to direct writing technology at a micro-scale level. In particular, the invention is directed towards a fluid dispensing system which applies micro-scale patterns on surfaces of medical devices.
2. Description of the Related Art
Direct-write technology with a dynamic fluid dispensing system has been successfully used for precision material placement in manufacturing a variety of products. Utilizing a two-axis positioning system, it has demonstrated capabilities for drawing lines and serpentine traces with width less than 50 microns on a wide range of substrates with and without complicated topologies Almost any material can be dispensed, including thick-film cermet pastes for the high voltage resistor industry.
A key feature of the process is the “soft-contact” control of the pen tip that delivers the material directly to the target substrate. The pen is suspended at an optimum height by optically sensing its position and dynamically applying correction forces to the pen tip. When properly adjusted, the pen can float on the substrate surface, passing over previously deposited traces and asperities with near-zero contact force, being held aloft by a combination of capillary pressure and hydrodynamic pressure developed in the flowing liquid “ink” between the pen tip and substrate.
Current direct-write technology, such as in U.S. Pat. No. 4,485,387 to Drumheller, the entire contents of which being incorporated herein by reference, is limited by its available pen-tip height control mechanism. Thus, a need exists for a new design of pen-tip force control to allow for finer scale resolutions.
The art referred to and/or described above is not intended to constitute an admission that any patent, publication or other information referred to herein is “prior art” with respect to this invention In addition, this section should not be construed to mean that a search has been made or that no other pertinent information as defined in 37 C.F.R. §156(a) exists.
All U.S. patents and applications and all other published documents mentioned anywhere in this application are incorporated herein by reference in their entirety.
Without limiting the scope of the invention a brief summary of some of the claimed embodiments of the invention is set forth below. Additional details of the summarized embodiments of the invention and/or additional embodiments of the invention may be found in the Detailed Description of the Invention below.
A brief abstract of the technical disclosure in the specification is provided for the purposes of complying with 37 C.F.R. §1.72